ordinal number


: a number designating the place (such as first, second, or third) occupied by an item in an ordered sequence see Table of Numbers
: a number assigned to an ordered set that designates both the order of its elements and its cardinal number

Examples of ordinal number in a Sentence

Recent Examples on the Web Interestingly enough, Kruskal's tree theorem required non-finite mathmatics to prove, using advanced techniques such as transfinite arithmetic and ordinal numbers. Jay Bennett, Popular Mechanics, 20 Oct. 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ordinal number.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1607, in the meaning defined at sense 1

Time Traveler
The first known use of ordinal number was in 1607

Dictionary Entries Near ordinal number

Cite this Entry

“Ordinal number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ordinal%20number. Accessed 17 Jun. 2024.

Kids Definition

ordinal number

: a number indicating the place (as first, fifth, 22nd) of an item in an ordered sequence compare cardinal number see number

More from Merriam-Webster on ordinal number

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